Fig. 8.

Effects of S1P turnover and free fatty acids on lipid droplet formation, content, size, and autophagy as well as on lipid peroxidation in insulin-secreting INS1E cells. INS1E cells were incubated in the absence or presence of PA or OA (500 μM of each) for 24 h. Shown are (A) the gene expression of seipin by qRT-PCR, (B) gene expression of Dgat2 by qRT-PCR (Means ± SEM from n = 4–8 independent experiments), (C) representative Plin2, Plin3, and Plin5 WBs from four independent experiments, (D) quantification of the number and size of lipid droplets after exposure FFA from n = 4–7 independent experiments, (E) lipid droplets detection by OilRed staining, a representative picture from n = 4–7 independent experiments, Bars: 20 μm, (F) colocalization of lipids (LipidTox Green) with lysosomes (LysoTracker Red), Bars: 10 μm, (G) lipid peroxidation, Means ± SEM from four independent experiments. ANOVA followed by Bonferroni, ∗P < 0.05, ∗∗P < 0.01, ∗∗∗P < 0.001 versus untreated, #P < 0.05, ###P < 0.001 versus INS1E-ctr cells treated in the same way.